ADE AYEYEMI’S office in Lomé, the capital of Togo, is a good place to think about crossing borders. Ghana is ten minutes’ drive away. From his window the boss of Ecobank can watch trucks rumble along the seafront, some bound for Burkina Faso, a day’s journey, or Mali, perhaps another day on. At night, cargo ships twinkle offshore. From here Ecobank’s vision—“to integrate the continent”, Mr Ayeyemi says—is clear. Whether it will be profitable is less obvious.

Ecobank was founded in 1985 by business leaders with backing from the Economic Community of West African States, a regional bloc. It has branches in 33 countries, more than any other African bank (see chart). It is not alone in its ambitions. Nigeria’s United Bank for Africa (UBA) wants to make half its profits elsewhere in the continent by 2022. South Africa’s Standard Bank recently opened in Ivory Coast, its 20th African country. Moroccan banks are trekking across the Sahara.